HV Battery Control System - Diagnostics: Pre-Check

PRECAUTION
1. To distinguish a trouble and replace a defective part, take necessary preventive measures against an electric shock. See INTRODUCTION .
2. Some portions of the wiring harness in the THS vehicle have the circuits, to which a high voltage is applied. To prevent an electrical shock, be sure to observe the following:
  1. Wear insulated gloves during inspection.
  2. Remove a service plug and do not start any repair operation before 5 minutes have passed, then confirm that the voltage at the output terminals has dropped down to 12 V or less.
    
    Fig 1: Disconnecting Service Plug
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Use insulated tools during inspection.
  4. When disengaging wiring connectors, hold the connector bodies to avoid pulling the wires. When engaging wiring connectors, be sure to engage them securely.
3. Do not leave tools or parts (bolts, nuts, etc.) inside the cabin.
4. Do not carry metallic objects such as mechanical pencils or scales.

DIAGNOSIS SYSTEM

Description
- The HV Battery ECU has a self-diagnosis system by which malfunction in the computer itself or in Hybrid System is detected and the master warning light in the combination meter and the Hybrid system warning light in the multi-information display lights up.
  
  Fig 2: View Of Multi-Information Display
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- To check the Diagnostic Trouble Codes (DTC), connect the TOYOTA hand-held tester to the Data Link Connector 3 (DLC3) on the vehicle. The TOYOTA hand-held tester also enables you to erase the DTC and check freeze frame data and various forms of THS data.
  
  Fig 3: Connecting TOYOTA Hand-Held Tester To Data Link Connector 3
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- Freeze frame data:
Freeze frame data records the battery condition when a malfunction is detected.

When troubleshooting, this is useful for knowing the battery condition.
Check the DLC3.
The HV control ECU conforms to ISO 14230 for communication.

The terminal arrangement of the DLC3 complies with SAEJ1962 and matches the ISO 14230 format.

Fig 4: Identifying DLC3 Terminals

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

DLC3 TERMINALS CONNECTION/VOLTAGE-RESISTANCE SPECIFICATIONS

Terminal No.	Connection/Voltage or Resistance	Condition
7	Bus Line/Pulse generation	During transmission
4	Chassis Ground <--> Body Ground/1 Ω or less	Always
5	Signal Ground <--> Body Ground/1 Ω or less	Always
16	Battery Positive <--> Body Ground/10 - 15 V	Always

NOTE:

If your display shows UNABLE TO CONNECT TO VEHICLE when you have connected the cable of the TOYOTA hand-held tester to the DLC3, turned the motor switch ON and operated the tester, there is a problem in the vehicle or tool.

If communication is normal when the tool is connected to another vehicle, inspect the DLC3 on the original vehicle.
If communication is still not possible when the tool is connected to another vehicle, the problem is probably in the tool itself, so consult the Service Department.

INSPECT DIAGNOSIS
1. Check the auxiliary battery.
  1. Measure the voltage of the auxiliary battery.
    Voltage: 10 - 15 V
  2. Inspect the auxiliary battery, fuses, fusible links, wiring harness, connectors and ground.
2. Check the master warning light.
  1. Turn the ignition switch ON and confirm that the master warning light comes on.
    
    Fig 5: Master Warning Light Display
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    NOTE:
    If the master warning light does not come on, suspect a burnt fuse, burnt bulb, or open in wiring harness.
  2. When the "READY" light is ON, the master warning light should go off.
    
    Fig 6: READY Light Display
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  If the lamp remains on, the diagnosis system has detected a malfunction or abnormality in the system.
3. Check the DTC.
  1. Prepare a TOYOTA hand-held tester.
  2. Connect the TOYOTA hand-held tester to the DLC3.
    
    Fig 7: Connecting TOYOTA Hand-Held Tester To Data Link Connector 3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Turn the ignition switch ON and push the TOYOTA hand-held tester main switch ON.
  4. Use the TOYOTA hand-held tester to check the DTC and freeze frame data and note them down. (For operating instructions, see the TOYOTA hand-held tester operator's manual).
    Since the HV battery ECU stores DTC and freeze frame data, when troubleshooting, check all of the DTC, write down the freeze fame data and perform inspection according to the procedures of "Circuit Inspection".
    
    Because the HV battery ECU is communicating with the HV ECU, if any DTC is stored in the HV battery ECU, check and record DTC stored in the HV ECU (For tables for DTC, see PRE-CHECK ).
  5. See a related procedure to confirm details of the DTC.
4. Clear DTC after completion of repair.
  1. Connect the TOYOTA hand-held tester to the DLC3.
    
    Fig 8: Connecting TOYOTA Hand-Held Tester To Data Link Connector 3
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    
    NOTE:
    Before clearing, check that DTC for the HV battery ECU, DTC for the ECU which is related with freeze frame data and the freeze frame data are recorded.
  2. Operate the TOYOTA hand-held tester to erase the DTC.
CHECK FOR INTERMITTENT PROBLEMS
1. Perform a simulation test (See HOW TO PROCEED WITH TROUBLESHOOTING ) .
  NOTE:
  In the simulation test, reproduce the condition at trouble occurrence based on the customer's comments and the freeze frame data recorded with the DTC.
2. Check the connector and terminal (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ) .
3. Handle the connector (See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE ).

TOYOTA HAND-HELD TESTER DISPLAY ITEMS

TOYOTA hand-held tester display	Measurement Item
BATTERY SOC	Battery State of charge
ONB CHARGE TIME	Cumulative number of times of on-board equalizing charging
BATTERY LO TIME	Cumulative number of times of battery dies
DC INHIBIT TIME	Cumulative number of times of discharge inhibition
IB MAIN BATTERY	IB main battery current (with correction)
BATT BLOCK V#	Battery block voltage
BAT BLOCK MIN V	Battery block minimum voltage
MIN BAT BLOCK #	Minimum voltage battery block
BAT BLOCK MAX V	Battery block maximum voltage
MAX BAT BLOCK #	Maximum voltage battery block
BATT INSIDE AIR	Ambient temperature inside battery pack
BATTERY TOO HI #	Cumulative number of times of too-high battery voltage
VMF FAN VOLTAGE	Battery cooling fan voltage
AUX. BATT V	Auxiliary battery voltage
WIN	Charge restriction value
WOUT	Discharge restriction value
DELTA SOC	Difference between MAX. and MIN. values of SOC at every battery block.
SBLW FAN ST RQS	SBL cooling fan stop request signal
COOLING FAN HI	Cooling fan operation in high speed
COOLING FAN MID	Cooling fan operation in middle speed
COOLING FAN LO	Cooling fan operation in low
CCTL	Off-board equalizing charge control signal
EQCO DF RELAY	EQCO dead front relay
EQTR CHARGE ST	EQTR uniform charging start signal
ONBORD CHARGE	On-board equalizing charging status
PRE ONBORDE CH	Pre-On-board charging status
NORMAL STATUS	Normal status
INSIDE RESIST #	Inside resistance
BATT TEMP #	Battery temperature
ECU CODE	ECU code
IG OFF HOUR	Average time of IG OFF
IGON HOUR	Average time of IG ON
ET OFF CHG HR	Estimation of time to finish OFF BOARD
DTC	The number of stored DTC